1. Field of the Invention:
The present invention relates to a machining reforming apparatus for an electrode of a resistance welding apparatus such as a spot welding machine or the like.
2. Description of the Prior Art:
Generally in a welding machine, if an electrode a thereof is used repeatedly, the periphery of the front end surface thereof is deformed with an outwardly annular projecting portion b, as shown in FIG. 1, and if such a deformed electrode a is not removed, there is a change in the electric current density. Therefore, it is necessary that the electrode a be subjected, at repeated time intervals, to a machining reforming treatment for removing the projecting portion b. An apparatus for carrying out this treatment is disclosed in Japanese Unexamined Utility Model Application No. Sho 52-22423. In this apparatus, a rotary cutter is used which has a cavity form that is coincident with the form of the front end portion of the electrode. The electrode to be reformed may be cut from its periphery to its front end surface. This treatment, however, has the disadvantage that the front end surface of the electrode has a fine unevenness resulting from the cutting, and accordingly, it requires a finishing treatment, such as grinding, to the uneven front end surface after cutting for making the surface smooth. Thus, the amount of machining becomes comparatively large and consequently the useful life of the electrode is shortened.